From a hardware or software standpoint, it's a matter of how up-to-date and complete your system's OpenGL graphics system is.
From the user's viewpoint, if your OpenGL is broken or missing, you may get a message from SleepyHead telling you that. Or, if you, like me, have 6+ years old (really?) computer and video hardware, the text in the Daily Charts will be blocky and unreadable. It will be easy to tell that you need the BrokenGL version.

I use both, and for me there is no visual or speed differences using Sleepyhead. There are programs that support 3D that definitely make bigger demands on the video system and require open GL. FWIW, I kind of wish Mark had just distributed Broken GL as it works on more computers and the Open GL generates the majority of problems we deal with to support new users.

In terms of SleepyHead, it's better if you can use the OpenGL version. The OpenGL works better when it works, but may fail to run on some computers. Sometimes, SH will refuse to run and tell you to run the BrokenGL version.

If I recall correctly, the version of the software packages Mark used to generate the latest version of SleepyHead required a more recent version of OpenGL. Some computers either won't run the necessary version of GL, or don't have the correct version installed, so Mark made a "BrokenGL" version of SleepyHead. The "BrokenGL" version may have some problems or drawbacks, but it runs on some computers that the "OpenGL" version won't.

Get the free SleepyHead software here. Useful links.
Click here for information on the main alternative to CPAP.
If it's midnight and a DME tells you it's dark outside, go and check it yourself.

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